1. Field of the Invention
This invention relates to an injection molding machine comprising a horizontally operable clamping unit, a mold defining a parting line, an injecting unit, which is operable in a direction that is transverse to said parting line, a pedestal having vertical longitudinal walls, which define interior chambers and one of which is disposed on the operator's side, and a protective covering having two vertical protective doors, which are disposed over and extend parallel to said one longitudinal wall, one of said protective doors covering the region which contains the mold and the other covering the region of a plasticizing cylinder that is included in said injecting unit, said protective covering also comprising vertical columns, which are supported on the pedestal and carry stationary tracks for guiding the protective doors and which are spaced from a centrally disposed stationary protective carrier, which has approximately the same size as each of the protective doors.
2. Description of the Prior Art
A prospectus by Battenfeld Maschinenfabriken GmbH entitled "Flexible Production Systems" (issued in February 1985) discloses an automated injection molding system in which, as illustrated on page 4, above the tool closing unit carrying bars are provided which are connected with transverse elements. The carrying bars have track rails for protective slides which may be displaced on the track rails in the longitudinal direction of the machine.
It is further known--as illustrated, for example, on page 11 of the Battenfeld prospectus--to arrange above the tool closing unit on one side a sole carrying bar to provide travel for a sled to transport moldings in a demolding system. The sled is arranged asymmetrically relative to the longitudinal axis of the injection molding machine.
In an injection molding machine that is known from U.S. Pat. No. 4,775,309, the clamping unit is shielded also from above by a stationary protective hood, which is portal-like in cross section. This is also the case in the mold region of the clamping unit; that mold region is adapted to be covered by a laterally disposed vertical protective door and by a horizontal upper protective door. The protective doors are adapted to be moved from a protecting position to a position under the corresponding covering portions of the protective hood. A portal-like stationary carrying frame for the entire protective covering for the clamping unit is assembled from cast iron shapes, which are provided with relatively short sleeves for guiding the protective doors. Sliding rods provided on the protective doors are horizontally guided in the guide sleeves. The same remarks are applicable to the protective door which serves to cover the plasticizing cylinder on the operator's side and which cooperates with guide sleeves, carried by a vertical cast iron column. The sliding rods provided on all protective doors are spaced from the top and bottom longitudinal edges of said doors. In an injection molding machine which comprises such a protective covering, which is also known from U.S. patent application Ser. No. 290,225, the height of the protective covering associated with the clamping unit may be relatively small because an unauthorized reaching from above into those regions of the clamping unit in which an accident may occur will be prevented by the horizontal guard provided there.